Another one so you have a better idea:

Benefits

What it is doing to the body...

- it beats up the body part on which the hoop spins which results in muscle contraction to protect whatever is underneath. Hulahoopers have a pretty toned body usually because their muscles are used to the hoop travelling around, massaging them & the contractions result in improved tone, strength & endurance. So when we hulahoop we work a bit harder than many would think: 1. we have to move to keep the hoop going, 2. our muscles contract at the points where the hoop applies pressure on the body.

- let's not leave that pressure alone: manual therapy applies pressure on the body as well for benefits such as bringing fresh nutrient-rich blood into tissues & accelerating the excretion of waste products. The hoop does what a massage therapist's hands do to us - it rubs us all over. It is obviously a completely different sensation because we rarely hulahoop on a massage couch with relaxing music, candles & oils. Think of this as an invigorating & firm & sweaty massage.

- equilibrium: most of us tend to be stronger or smarter on one side because e.g. we like to write, text, kick on one side. This one-sidedness (is there a word like this?:)) can be amplified further with trauma: so if you have an injured leg or arm, you tend to overload the other side. When hooping this is a weakness & those who are very much one-sided will laugh a lot when the hoop goes bonkers. With time the hoop teaches all of us to be happy with both sides. It does not only improve our connections with our other side but other body parts, too - so if you cannot do fine movements with your feet,  shoulders, PELVIS... with the hoop you will learn how to.

Difference

So many hoopy things are going on but they all differ a bit:

Native American Hoopdance: as in video above

Hulahooping: something like what most of us think of when hearing the word "hulahoop": spin it around the waist, maybe hips or knees & that's pretty much it.

Hulaerobics: the kind of thing you are likely to find in a studio class in gyms & health clubs. It is an exercise class with an aerobics instructor doing squats, lunges, box-steps etc. with a hulahoop spinning around the waist. This is done with 1 hoop (often heavily weighted).

Hoopdancing: when someone dances with a hulahoop to music - linking one move or trick to the other flawlessly & gracefully. This is done with 1 or 2 hoops, sometimes more - these hoops are quite lightweight but still large.

Hulahoop act: the circus act when one trick follows the other, there can be music but not much dance-related movement. The tricks are ever so spectacular & often you see contortion & acrobatic gymnast skills & an awful lot of hulahoops.